This app is exactly what I wanted: it tracks protein and nothing else. It's not weighed down by the be-everything-to-everyone ethos of so may other health-related apps. That said, it has some minor problems.
You can't add meals for the previous day after midnight (though you can just edit an old meal to add new items and change the total grams of protein).
Some areas feel unfinished, like when editing a meal it lists the day of the week then literally, "Month, Year" (the month and year do not populate).
It sometimes crashes.
I would pay $5 for a version with minor fixes.
I would pay $10 for a Mac version that syncs with the iOS version.
As is, it's great for daily tracking. I use it for every single thing I eat.
I love this app and hope to see continued development.